编译这个线程的程序为什么出错？

andy007

/tmp/ccGycMxS.o(.text+0x21): In function `main':
: undefined reference to `pthread_create'
/tmp/ccGycMxS.o(.text+0x5c): In function `main':
: undefined reference to `pthread_create'
/tmp/ccGycMxS.o(.text+0x8f): In function `main':
: undefined reference to `pthread_join'
/tmp/ccGycMxS.o(.text+0x9f): In function `main':
: undefined reference to `pthread_join'
collect2: ld returned 1 exit status

1. 
   
2. #include <stdio.h>
   
3. #include <stdlib.h>
   
4. #include <pthread.h>
   
5. 
   
6. void task1(int *counter);
   
7. void task2(int *counter);
   
8. void cleanup(int counter1, int counter2);
   
9. 
   
10. int g1 = 0;
    
11. int g2 = 0;
    
12. 
    
13. int main(int argc, char *argv[])
    
14. {
    
15.         pthread_t thrd1, thrd2;
    
16.         int ret;
    
17. 
    
18.         ret = pthread_create(&thrd1, NULL, (void *)task1, (void *)&g1);
    
19.         if (ret) {
    
20.                 perror("pthread_create: task1");
    
21.                 exit(EXIT_FAILURE);
    
22.         }
    
23.         ret = pthread_create(&thrd2, NULL, (void *)task2, (void *)&g2);
    
24.         if (ret) {
    
25.                 perror("pthread_create: task2");
    
26.                 exit(EXIT_FAILURE);
    
27.         }
    
28. 
    
29.         pthread_join(thrd2, NULL);
    
30.         pthread_join(thrd1, NULL);
    
31. 
    
32.         cleanup(g1, g2);
    
33. 
    
34.         exit(EXIT_SUCCESS);
    
35. }
    
36. 
    
37. void task1(int *counter)
    
38. {
    
39.         while (*counter < 5) {
    
40.                 printf("task1 count: %d\n", *counter);
    
41.                 (*counter)++;
    
42.                 sleep(1);
    
43.         }
    
44. }
    
45. 
    
46. void task2(int *counter)
    
47. {
    
48.         while (*counter < 5) {
    
49.                 printf("task2 count: %d\n", *counter);
    
50.                 (*counter)++;
    
51.         }
    
52. }
    
53. 
    
54. void cleanup(int counter1, int counter2)
    
55. {
    
56.         printf("total iterations: %d\n", counter1 + counter2);
    
57. }
    

复制代码

lucifer

加上-lpthread试试

andy007

thanks!